Larry Bird, who serves in a special advisory role for the Pacers, was aboard the somber team plane. And, yet, the three-time NBA champion refrained from addressing the players on squandering such a precious postseason opportunity.

"No, I don't say anything,'' Bird told ESPN. "Our coach handles that. Besides, you could see it on their faces.''

The Pacers led by 11 points in the fourth quarter but imploded down the stretch with a series of questionable decisions, none more incomprehensible than a Wesley Matthews cross-court pass with 12.1 seconds left to Bojan Bogdanovic, who stood with his back to the ball and turned just in time to watch the pass sail out of bounds untouched. This happened, mind you, as Indiana emerged from a timeout.

At that juncture, the Pacers were only down 3.

An ill-advised foul, another turnover and unpleasantries exchanged among visibly frustrated Pacer players ensued. They had bungled a winnable game that would have enabled them to seize home-court advantage, and it showed.

"If you're gonna have a meltdown, you've got to stick together,'' Bird explained. "You can't b---- at the referees. You gotta get back after a miss. Every possession is so huge in the playoffs.

"So, Kyrie Irving hits a big shot. You've got to expect that. You gotta come down and set picks, rebound the ball, help each other out. And if you don't, it's gonna kill you.''

Larry Bird has some words of wisdom for the Pacers: "The main thing is they've got to be mentally tougher." Greg M. Cooper-USA TODAY Sports

The Pacers began the season with high hopes, racing out to a 30-16 record by late January, but then their franchise player Victor Oladipo ruptured his quad tendon and was lost for the season. Prognosticators predicted a free fall, but Indiana stubbornly hung onto its top-four seeding until the final 10 days of the season. In the meantime, scoring has become excruciatingly more difficult, and only an elite defense has enabled the Pacers to stay afloat.

"Obviously when Victor went down, it changed everything,'' Bird said. "I thought we could match last year's victory total, and even after we lost him, we did that. The way these guys rallied was amazing. [Pacers president of basketball operations] Kevin Pritchard and [coach] Nate [McMillan] have done a great job with them.

"They're well-coached, and when they lose, they fight back and find a way to win. That's who they are.''

Bird said that while the Indiana players were obviously distraught in the wake of Game 2's embarrassing finish, he expects McMillan, whom he calls "an old-school guy who takes care of things," to figure out how to get them to re-group.

"The main thing is they've got to be mentally tougher,'' Bird said. "I told Kevin before the series, 'Free throws are going to be your downfall.' One guy starts missing them and they all miss them.'' (Indiana ranked 22nd in the NBA in free throw percentage at .749 during the regular season, and ranked 25th in free throws attempted.)

Bird said he was surprised to learn following Game 2 that Domantas Sabonis, who has become a trusted sixth man for the Pacers, had just 1 point. He's a player, Bird said, who has exhibited grit throughout the year.

Bird delighted Celtics fans by making a rare trip to the TD Garden for Games 1 and 2. He does not travel often, particularly since serious back problems that plagued him near the end of his career have made commercial travel prohibitive. He said he considered making a trip to Boston last year for a regular-season game, but decided against it, mindful that it was Pritchard's first full season as his successor in the basketball operations job. "I didn't want to upstage Kevin,'' Bird explained.

It was Pritchard, Bird said, who urged him to accompany him to Boston this time around. Bird received a thunderous ovation in the third quarter of Game 1 when the giant video screen flashed his image. And, when he stood to acknowledge the fans, the building shook as the vintage "Lar-ry!" chants began in earnest.

"I think I've told you this before,'' Bird said. "When I first went out there [to Boston], Dinah and I really liked it. We were going to stay the rest of our lives.

"But we knew once the season started it would never be possible. We had this vision of going to Red Sox games in the summer. Well, we went to some Red Sox games and it was out of control. I got mobbed going in, coming out and the whole time in between. We didn't understand that's how it would be, all the time, every day.

"I always say my time in Boston was the greatest experience of my life. It's an experience I wish everyone could have. And going back there brings back a lot of memories.''

Bird lived in Brookline during his entire playing career. When people drove past his home and tooted their horn, he'd turn to Dinah and say, "There go the fans.''

"It was the perfect area for me,'' Bird said. "Everyone knew where I lived, but hardly anyone bothered me. I would say over a 14- or 15-year period, only about two or three people ever came to the door. When I was out washing the car, they might stop and try to talk to me, but for the most part the people there treated me with great respect.

"You win a championship in Boston and that's what you'll get, whether you're the top player or the second or third player. They're just great fans. They were great again [Wednesday night].''

Bird insists his Pacers are not out of this series yet. Boston has been vulnerable on the road all season, and Indiana will have success, he predicts, if it forces tempo, plays a physical brand of basketball and, most importantly, conquers the mental component in tight games.

"That,'' said Bird, "is how great players separate themselves from everyone else.''